| Certified value, µg∙g−1 | Acceptance limits, µg∙g−1 | Cr(VI) by MPC-IC-MS/MS, µg∙g−1 | Cr(VI) by DPC-UV-VIS, µg∙g−1 | Cr(VI) by SID-IC-MS/MS, µg∙g−1 |
NIST | 551.2 ± 34.5a | - | 612.1 ± 32.7a | 494.0 ± 23.8a | - |
Phenova | 147 | 46.9 - 224b | 139.1 ± 17.5a | 108.0 ± 5.0a | - |
Fluka | 153 ± 6 | 56 - 250b | - | - | 161 ± 6a |